WASHINGTON, DC – MARCH 31: U.S. Secretary of Defense Robert Gates testifies during a hearing before the House Armed Services Committee March 31, 2011 on Capitol Hill in Washington, DC. The hearing was to examine the ongoing military operation in Libya.

Former U.S. Defense Secretary Robert Gates on Tuesday warned that Russia’s invasion of Ukraine is part of a broader push to create a pro-Russia bloc and called for a stronger U.S.-European strategy of economic sanctions with military backup.

Otherwise, Russian President Vladimir Putin and other aggressors will disrupt stability, Gates said in a Denver Post interview.

“We need to see this as not just a singular act by Putin but rather as a continued effort to create a pro-Russia bloc of states on Russia’s periphery,” Gates said. “We don’t need to demonize Putin. We need to look clearly at what he has done — both inside Russia and with respect to his neighbors.”

Americans have an interest “in countries not invading other countries and changing borders by force,” Gates said in the interview, by phone from his home in Washington state.

Russia’s takeover of Crimea sets “a dangerous precedent in a world that faces as much turmoil and instability as we face now,” Gates said. “It is the principle of noninterference and nonaggression on states on your border that is the principle that has to be upheld.”

Russian actions also threaten the post-Cold War norm of nations choosing their own alliances and economic partners — as Ukraine tried to do, he said. “If those principles are undermined, then the prospect of stability in Europe, which has been bright … is seriously endangered.”

A U.S.-European counterstrategy should include an increased military presence “to reassure our allies, who are nervous,” he said, adding he does not believe Russia intends to invade Poland or Bulgaria.

Next targets probably will be Baltic states, vulnerable to economic and cyberattacks, he said.

And the initial Western response, trying to limit travel and freeze accounts of high officials, “is not very meaningful,” he said.

Gates outlined a strategy of “curtailing investments,” closing relations with Russian banks, reducing Europe’s dependence on Russian oil and gas, and helping Baltic states Latvia, Estonia and Lithuania. He favors “the same sanctions we applied against Iran.”

Europe probably won’t back robust sanctions, Gates said.

U.S. action alone “could do serious damage with sanctions on the banks, but virtually all the other economic measures would require Europe’s cooperation and participation.”

Putin’s pivot toward wielding raw power must be seen in the context of Russia’s 2008 invasion of Georgia and relations with Moldova and Armenia, where Russian speakers reside.

U.S. military options to deter Russian forces are limited, and the 1994 U.S.-UK-Russia agreement on Ukraine “is not a security guarantee.”

But U.S. reluctance to supply Ukraine with weapons may change after elections in Kiev, Gates said.

“(Russia’s actions) are serious. They have long-term consequences. If serious actions are not taken in response, then we are going to see Putin act aggressively in other places as well,” he said. “If the West is unwilling to act, then you will also see other aggressors.”

Bruce Finley covers environment issues, the land air and water struggles shaping Colorado and the West. Finley grew up in Colorado, graduated from Stanford, then earned masters degrees in international relations as a Fulbright scholar in Britain and in journalism at Northwestern. He is also a lawyer and previously handled international news with on-site reporting in 40 countries.

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